The invention relates to a circuit breaker comprising contacts, a contact actuating mechanism and an electronic trip device supplying a tripping signal to a control device of the actuating mechanism to bring about opening of the contacts in the event of a fault occurring on the power supply system to be monitored, the mechanism control device comprising means for locking the actuating mechanism in the open position, and the trip device comprising means for detecting the type of fault.
Some conventional circuit breakers comprise locking means designed to lock the contacts in the open position. This is generally achieved by means of a key acting mechanically on the actuating mechanism or on its control and preventing closing of the contacts so long as it is in the locked position.
The object of the invention is to improve this type of circuit breaker so as to adapt it to better suit the user's requirements and to favor, depending on the installation in which it is incorporated, either continuity of operation or safety.